*{
    padding:0;
    margin: 0;
    list-style: none;
    box-sizing: border-box;
}

.box{
    width: 500px;
    height: 300px;
    border:1px solid #CCC;
    margin: 30px  auto 0;
    display: flex;
}

.nav{
    width: 100px;
    border-right: 1px solid #CCC;
}

.nav span{
    display: block;
    height: 40px;
    border-bottom: 1px solid #CCC;
    text-align: center;
    line-height: 39px;
}



.active{
    background: orangered;
    color: #FFF;
}
.cons{
    flex:1
}
.cons > div{
    display: none;
}

.show{
    display: block!important;
}